Battery pack

Abstract

A battery pack includes: a case including a cell accommodation portion to accommodate a battery cell; and output terminals protruding upward from a first side of an upper portion of the case, and the output terminals protrude from first height-difference surfaces stepped downward from a first surface that is an uppermost surface of the first side of the case. The structure of the battery pack is improved such that the output terminals protruding outward may be effectively protected from impactive force, and the battery pack may be combined with other battery packs having substantially the same shape to flexibly cope with high-output, high-capacity demand.

What is claimed is: 
     
         1 . A battery pack comprising:
 a case comprising a cell accommodation portion to accommodate a battery cell; and   output terminals protruding upward from a first side of an upper portion of the case,   wherein the output terminals protrude from first height-difference surfaces stepped downward from a first surface that is an uppermost surface of the first side of the case.   
     
     
         2 . The battery pack of  claim 1 , wherein the output terminals comprise first and second output terminals, and
 the first height-difference surfaces are on both outermost lateral sides along the first side in a left-right direction of the battery pack in which the first and second output terminals are spaced apart.   
     
     
         3 . The battery pack of  claim 1 , wherein the first surface comprises a pair of first surfaces on both sides of a second height-difference surface stepped downward from the pair of first surfaces, the second height-difference surface being between the pair of first surfaces. 
     
     
         4 . The battery pack of  claim 3 , wherein the second height-difference surface is at a center position of the first side in the left-right direction of the battery pack. 
     
     
         5 . The battery pack of  claim 3 , further comprising at least one of a communication terminal and a pressure regulating valve protruding from the second height-difference surface. 
     
     
         6 . The battery pack of  claim 5 , wherein a pair of barrier ribs is on the second height-difference surface, at least one of the communication terminal and the pressure regulating valve being between the pair of barrier ribs. 
     
     
         7 . The battery pack of  claim 3 , wherein the first and second height-difference surfaces are stepped downward from the first surface such that the first height-difference surfaces are lower than the second height-difference surface. 
     
     
         8 . The battery pack of  claim 3 , wherein the first height-difference surfaces are on both lateral outer sides of the pair of first surfaces. 
     
     
         9 . The battery pack of  claim 1 , wherein the case comprises a front case and a rear case facing each other and coupled to each other in a front-rear direction, and
 the rear case is thicker than the front case in the front-rear direction.   
     
     
         10 . The battery pack of  claim 9 , wherein the output terminals are on the rear case at positions biased toward the front case. 
     
     
         11 . The battery pack of  claim 10 , wherein the output terminals are at center positions in a thickness direction of the battery pack parallel to the front-rear direction. 
     
     
         12 . The battery pack of  claim 1 , wherein a second surface inclined with respect to the first surface is on a second side of a lower portion which is opposite the first side of the battery pack. 
     
     
         13 . The battery pack of  claim 12 , wherein support ribs protrude from the second surface of the second side to form a flat bottom surface as a support base of the battery pack. 
     
     
         14 . The battery pack of  claim 1 , wherein the case comprises a front case and a rear case facing each other and coupled to each other in a front-rear direction, and
 front assembly portions and rear assembly portions are respectively on a front side of the front case and a rear side of the rear case, the front assembly portions being embossed on the front side of the front case, the rear assembly portions being engraved on the rear side of the rear case.   
     
     
         15 . The battery pack of  claim 14 , wherein the front assembly portions and the rear assembly portions are at corresponding positions and have complementary shapes. 
     
     
         16 . The battery pack of  claim 14 , wherein the front assembly portions and the rear assembly portions are respectively at four corner positions of the front side of the front case and four corner positions of the rear side of the rear case. 
     
     
         17 . The battery pack of  claim 1 , wherein the case comprises a front case and a rear case facing each other and coupled to each other in a front-rear direction, and a front rib and a rear rib respectively protrude from a front side of the front case and a rear side of the rear case. 
     
     
         18 . The battery pack of  claim 17 , wherein the front rib comprises a pair of first front ribs and a pair of second front ribs, each pair extending on the front side of the front case in mutually-facing directions from a first side of an upper portion and a second side of a lower portion of the front case, and
 the first and second front ribs are at first and second positions that are different from each other in a left-right direction of the battery pack.   
     
     
         19 . The battery pack of  claim 18 , wherein the rear rib comprises a pair of first rear ribs and a pair of second rear ribs, each pair extending on the rear side of the rear case in mutually-facing directions from a first side of an upper portion and a second side of a lower portion of the rear case, and
 the first and second rear ribs are at first and second positions that different from each other in the left-right direction of the battery pack.   
     
     
         20 . The battery pack of  claim 19 , wherein the first positions are relatively adjacent to a first output terminal of the output terminals in the left-right direction of the battery pack in which the first output terminal and a second output terminal of the output terminals are spaced apart, and
 the second positions are relatively adjacent to the second output terminal in the left-right direction of the battery pack.